Last week, King County’s traffic engineers stood before a hearing examiner and defended their record on managing growth—a record that some residents of the county have found to be somewhere between poor and dismal. While the Department of Transportation staffers acquitted themselves well on some points, their testimony shed damning light on the county’s overall approach, making it clear that the official promise of Growth Management is being given the lie by the actual policies, which turn out to be loophole-laden.

As reported here last week, the county’s system for approving new housing developments is subject to a citizen challenge that could force big changes, perhaps even turn back the clock on projects already under way. Scott Hamilton, a resident of the Sammamish Plateau, is appealing the “concurrency” certificate that the county issued to the Greens at Beaver Crest, a big new development going up near his home. A concurrency certificate—the first step in getting a housing project approved—is the county’s determination that the project will not overly strain the surrounding road system; under the state’s Growth Management Act, cities and counties are only supposed to approve as much development as their transportation infrastructure can handle.

The act, however, does not specify what is an acceptable level of traffic, leaving that up to local officials. As a designated “urban” zone, the Plateau has a fairly lax traffic standard, which the King County Council relaxed even further approximately two years ago. The act also specifies that housing developments are not to be measured against the present-day road system but against the improved or expanded systems that will be on line six years ahead, when the development presumably would be finished. Thus small changes in the county’s road-building plans can unleash a flood of new housing approvals.

Activists on the Sammamish Plateau have long been convinced the county was cooking the books in some way that allowed it to green-light hundreds of new developments despite the Plateau’s already fearsome traffic and the precious little expansion scheduled for its narrow rural roads. One band of local growth opponents has spent the better part of the past year haranguing county officials over what it claims were low-ball traffic estimates used to grant concurrency to a pair of giant Plateau developments, Northridge and Blakely Ridge, back in 1995.

But Hamilton’s appeal is the first time the county DOT has been forced to hand over its “black box”: the computer program that forecasts a development’s impact on local roads, then issues a score determining whether the project passes concurrency. Hamilton brought in Bellevue traffic consultant Joe Savage to examine the county’s software, and Savage found it to be riddled with “errors.” In testimony before the hearing examiner last month, Savage contended that the county did not update its model sufficiently to keep up with local growth and that its traffic analysis techniques all served to minimize the projected impact of new developments.

In a point-by-point rebuttal last week, Dick Etherington, a senior official at the DOT, insisted that many of the alleged “errors” were simply “differences in professional judgement,” and that others were just cases of Savage misunderstanding the county’s approach. Robert Johns, an attorney representing the Beaver Crest developer, tried to suggest that some aspects of the concurrency test can serve to overestimate traffic as well.

Yet the county had no credible defense against Savage’s most disturbing allegation. Savage found that when the computer model comes up with a forecast that is above the acceptable threshold for a certain road, the program automatically lowers the number. In other words, if the forecast shows a development sending a road more than 10 percent over its capacity—at which point, county law imposes certain restrictions on the developer—the model simply knocks that score down. Etherington conceded that this was the case, at least for the concurrency test that was run on Beaver Crest. But he claimed the approach was legitimate because people start commuting at different times once a road gets overcrowded.

However plausible that explanation, it amounts to an admission that the county’s concurrency system is failing to keep its growth-regulating promise—a point not lost on Hearing Examiner Stafford Smith. Contrary to the supposed requirements of Growth Management, the concurrency rules allow roads to be loaded up virtually without limit, thus eliminating any barriers to approval of new housing projects. Under the county’s rules, a development can pass concurrency so long as it does not send more than one-third of its total car trips onto an overloaded road, going the peak direction, during the peak hour of the evening commute. Since affluent households like those on the Plateau generate, on average, more than 10 car trips per house per day, it is unlikely that one-third of those will be in the same direction, on the same road, during the same hour. And so long as a development does not hit that cut-off, it will still get concurrency approval even if the roads it feeds are already forecast to be choking on traffic.

In the case of the Beaver Crest project, the computer model determined that its hundreds of new homes would help to clog State Route 202 to a point 100 percent over the road’s actual car-carrying capacity. But that was not enough to stop the project from getting its concurrency certificate. “Doesn’t that [100 percent figure] tell you that you’ve approved more projects than the road can handle?” asked hearing examiner Smith. “Yes,” Etherington replied. “But none were approved in error.” Welcome to the Growth Management Wonderland.

The County Council is now considering changes to the one-third rule. But that will be too late for the Sammamish Plateau, where thousands of new homes have already passed concurrency and are on their way. Even county officials now concede that they bungled the job of managing growth in the formerly bucolic area. It is now up to the hearing examiner to determine whether history will be revised. His decision on the Beaver Crest appeal—and the overall validity of the county’s approval process—will probably come in another month.